Gfan is a software package for computing Groebner fans and tropical varieties. These are polyhedral fans associated to polynomial
ideals. The maximal cones of a Groebner fan are in bijection with the marked reduced Groebner bases of its defining ideal. The
software computes all marked reduced Groebner bases of an ideal. Their union is a universal Groebner basis. The tropical variety of
a polynomial ideal is a certain subcomplex of the Groebner fan. Gfan contains algorithms for computing this complex for general
ideals and specialized algorithms for tropical curves, tropical hypersurfaces and tropical varieties of prime ideals. In addition to the
above core functions the package contains many tools which are useful in the study of Groebner bases, initial ideals and tropical
geometry. Among these are an interactive traversal program for Groebner fans and programs for graphical renderings.
For ordinary Groebner basis computations Gfan is not competitive in speed compared to programs such as CoCoA, Singular and
Macaulay2.
68adb1065a